A sensitive, selective and reproducible high-performance liquid chromatographic assay for the simultaneous determination of metoprolol and alpha-hydroxymetoprolol in plasma was developed with (+/-)-ethyl-2-(4-(3-isopropyl-amino-2-hydroxy-propoxy)phenyl)-ethyl carbamate as the internal standard. Samples were acidified and subjected to an organic wash to remove interfering neutral and acidic components. Final extraction is made from the alkalinized aqueous phase with methylene chloride. The samples were chromatographed on a microparticulate silica gel column with fluorescent detection. Sensitivity was 3 ng/ml for metoprolol and 12.5 ng/ml for alpha-hydroxymetoprolol. Specificity was established by comparison of retention times of samples with standard materials. A typical absorption/disposition profile for metoprolol and alpha-hydroxymetoprolol is presented for one subject who received 50 mg of metoprolol tartrate (Lopressor).
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/s0378-4347(00)80434-x | DOI Listing |
Expert Rev Clin Pharmacol
January 2025
Department of Internal Medicine and Cardiology, University Hospital Ostrava, Ostrava, Czech Republic.
Background: The cardioselective β-1 receptor antagonist metoprolol is used to treat heart failure. It is metabolized in the liver, primarily by cytochrome 2D6.
Research Design And Methods: In this study, trough serum concentrations of metoprolol and its metabolite α-hydroxymetoprolol were measured in patients with heart failure with reduced ejection fraction.
Pharmacogenomics J
April 2024
Institute of Molecular Toxicology and Pharmacology, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang, China.
Clin Pharmacokinet
August 2023
Division of Clinical Pharmacology and Toxicology, University Hospital Basel, 4031, Basel, Switzerland.
Background And Objective: The impact of liver cirrhosis on the activity of UDP-glucuronosyltransferases (UGTs) is currently not well characterized. We investigated the glucuronidation capacity and glucuronide accumulation in patients with liver cirrhosis.
Methods: We administered the Basel phenotyping cocktail (caffeine, efavirenz, flurbiprofen, omeprazole, metoprolol, midazolam) to patients with liver cirrhosis (n = 16 Child A, n = 15 Child B, n = 5 Child C) and n = 12 control subjects and obtained pharmacokinetic profiles of substrates and primary metabolites and their glucuronides.
Clin Pharmacokinet
July 2022
Division of Clinical Pharmacology and Toxicology, University Hospital Basel, 4031, Basel, Switzerland.
Background: Activities of hepatic cytochrome P450 enzymes (CYPs) are relevant for hepatic clearance of drugs and known to be decreased in patients with liver cirrhosis. Several studies have reported the effect of liver cirrhosis on CYP activity, but the results are partially conflicting and for some CYPs lacking.
Objective: In this study, we aimed to investigate the CYP activity in patients with liver cirrhosis with different Child stages (A-C) using the Basel phenotyping cocktail approach.
Clin Transl Sci
April 2022
Faculty of Pharmacy, Université de Montréal, Montreal, Quebec, Canada.
Large, observational genetic studies are commonly used to identify genetic factors associated with diseases and disease-related traits. Such cohorts have not been commonly used to identify genetic predictors of drug dosing or concentrations, perhaps because of the heterogeneity in drug dosing and formulation, and the random timing of blood sampling. We hypothesized that large sample sizes relative to traditional pharmacokinetic studies would compensate for this variability and enable the identification of pharmacogenetic predictors of drug concentrations.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!